Can't say much more than that! Bought it to a replace a cheap plastic pump I had which worked fine but the valves on my balls went after a bit and I think it was the tapered shaped of the plastic pump stressing the diameter of the valve too much - this one has a thin metal needle which is straight all the way down, so doesn't force the valve open too wide, so I'm hoping that solves it.
Anyway - this pumped the balls up fine and still solid after a week and a couple of matches.
Only fault I have with it is you have to keep the tubes with the needles on with the pump: there's nowhere to clip or attach them. Easy enough to stick a rubber band round to hold things together, but would have been nice if they could have found some way to slot the tube into the handle or something.